Thursday, 16 July 2015

Early diagnosis of cancer can save lives, yet so many people wait before reporting important symptoms. This is an issue where psychology can make a major contribution by helping to explain why some patients delay reporting their symptoms to a clinician. A pilot study published recently in Psychology and Health uses an unusual approach for this purpose, specifically in the context of skin cancer, by asking patients to draw their melanomas.

Suzanne Scott at Kings College, London and her colleagues recruited 63 skin cancer patients (average age 64), around half of whom had a thinner melanoma, and half a thicker melanoma (prognosis is poorer for the latter group). Four of the patients had had their melanomas spotted opportunistically by a clinician; the others had waited between 1 week and 303 weeks before reporting their first symptoms to a clinician.

All the patients were asked to produce annotated drawings of their melanoma as it looked when they first noticed it, and how it changed over time. Fifty-three of the patients agreed to do this (three had their wife or daughter produce the drawings), while four patients were unwilling or unable to do the drawing. Overall, this suggests that the idea of drawing their symptoms is acceptable and practical for most patients. Some patients drew one picture, others did several. Men tended to produce more drawings than women. In all, 137 drawings were produced by 53 patients.

Image: participant drawing from Scott et al, 2015.

The researchers said the level of detail produced in the drawings shows that most patients tend to pay attention to their skin changes rather than dismissing them, but that they often don't act on the changes. This is an important insight because it implies that public health interventions need to do more to educate people about the meaning of their skin changes and when it is appropriate to seek help.

Another key finding was that patients' drawings correlated in size with their actual melanomas (as measured in histology photos), and yet there was no correlation between size of drawings and the time taken to seek medical help. The researchers said this further suggests that it is likely patients' interpretations of the meaning of their symptoms, rather than their perception of the physical nature of the symptoms per se, that explains their decisions as to whether or not to seek help. It's also notable that patients often depicted changes in size and colour in their drawings (two key features that are important for melanoma diagnosis), but other important diagnostic factors including shape and border irregularity were rarely depicted.

The study is limited by the small sample size and the reliance on asking patients to remember how they perceived their melanomas in the past. Nevertheless, Scott and her team said these preliminary results are encouraging and they suggest patient drawings could be a useful adjunct to standard interviews, furthering our understanding of how to achieve more early diagnoses. "Patient drawings add a deeper understanding of patient perception of their lesion," they said, "... [drawings] can facilitate discussion of symptoms perception and appraisal."